The KwakiutI recognized one social unit larger than the tribe-the confederacy, which was a cluster of loosely knit, informally related neighboring tribes who interacted with themselves more often than between other tribes.

A. tribes who interacted with themselves more often than between

B. tribes who interacted among each other more often than among

C. tribes who interacted with one another more often than with

D. tribes, interacting among each other more often than between

E. tribes, interacting among one another more often than with


OA C


Is there no need of comma before who?? as who is modifying tribes.